The Khwarezmian script is not yet in Unicode. The script has a tentative allocation at U+10EE0..U+10EFF in the Roadmap to the SMP for the Unicode Standard.
One document towards encoding the script has been submitted to the Unicode Technical Committee:
2017-01-31 Preliminary proposal to encode the Khwarezmian script in Unicode — Anshuman Pandey ( L2/17-054)
Recommendations to UTC #152 July-August 2017 on Script Proposals ( L2/17-255) (See point 19.)
UTC #152 Minutes ( L2/17-222) (See C.23 for decision and action items)